To celebrate Positive Thinking Day, an unofficial holiday that lands on September 13, Life is Good—the company behind those distinctively cheerful shirts, hats, and more—conducted the Life is Good Optimism and Positivity Index to determine which lifestyle habits and life stages are most likely to be linked to a positive outlook on life.

The survey asked 3,000 individuals from across the United States how optimistic they were—and a whopping 85 percent considered themselves to be positive thinkers. Compared to five years ago, 44 percent of people are more optimistic now than they were then, while 32 percent are less so.

By analyzing responses, the Index found connections between optimistic people and their habits and characteristics—and found which of these can be detrimental to a positive outlook on life. If you already have these characteristics or habits, you’re more likely to be optimistic, though of course that’s not a guarantee of a sunny perspective. If you don’t, you may find something to work toward, and find yourself more optimistic in the process. After all, like everything else in life, being optimistic takes a little work. (And optimism may help you live longer, so it’s worth it.) According to the Life is Good Optimism and Positivity Index, optimistic people are:

1. 60-69 Years Old
All right, you can’t do much to obtain this characteristic of optimistic people beyond wait for the years to go by, but knowing that most older people are more optimistic may give you something to look forward to, boosting your optimism levels in the meantime. According to the survey’s results, 60- to 69-year-olds are more likely to be optimistic than 18- to 29-year-olds.

5. Not Glued to Screens
Using technology for more than ten hours a day, outside of work, are often more pessimistic than those who don’t; most optimistic people manage to get away from screens for at least part of every day.